There are a few options, but it depends.
If you work for an organization that does Azure work and has an agreement with Microsoft, there's a good chance the organisation has access to Visual Studio Subscriptions, that includes free Azure credit you can leverage.
Some organisations may have an azure subscription or two, dedicating for testing (ie a sandbox) that you could request a Resource Group, to test.
If your a student there's a few options:
Some Microsoft Learn modules, also include a Sandbox to do certain tasks, so you don't need your own Azure subscription to learn.